Effect of supercritical carbon dioxide as an exfoliation aid on bio-based polyethylene terephthalate glycol-modified/clay nanocomposites

Bio-based PETG (bio-based glycol modified polyethylene terephthalate, Ecozen T95) / clay (organo-modified montmorillonite, OMMT, C10A) nanocomposites were prepared by co-rotating twin screw extruder attached with supercritical carbon dioxide (scCO 2 ) injection system. The effects of nano-clay and scCO 2 on the properties of PETG/clay nanocomposites were investigated by measuring thermal, rheological, tensile, impact, and barrier properties. The thermal and mechanical properties decreased with increasing nano-clay content, but they recovered or even exceeded the properties of neat PETG as scCO 2 was added. It was verified due to a good dispersion of the nano-clay in PETG matrix for PETG/clay nanocomposites by XRD, SEM, and TEM. It was thought that scCO 2 could be an effective exfoliation agent for many nanocomposites systems as well as for bio-based PET/clay nanocomposites.